Showing papers by "Bruno de Sousa published in 2010"
TL;DR: At the initial stage of the integrated malaria control programme, IRS contributed to the visible effect on the rapid reduction of malaria morbidity and mortality, while this programme highlights an urgent demand for the improvement of other measures, particularly promotion of LLINs usage, with close monitoring of asymptomatic carriers and with ACT treatment in malaria transmission hotspots.
Abstract: Background
Plasmodium falciparum is the major cause of malaria infection in the island of Sao Tome, in the Republic of Sao Tome and Principe (STP), with an incidence of 40 - 50% before 2004. Since 2004, through the coordination of the Ministry of Health of STP and their Centro Nacional de Endemias (CNE), an integrated malaria control programme has been intensively deployed on the island of Sao Tome. Malaria morbidity and mortality decreased by 95% after three years of effective intervention. In the low transmission settings, however, malaria seasonal fluctuation can be a potential problem directly related to epidemics if ongoing control measures are interrupted. Studies on a number of associated factors with malaria epidemics and the measures taken to respond to outbreaks are presented.
28 citations
TL;DR: The simulation study shows that, under the most commonly used and generally accepted therapy approaches for HDV infection, LMV monotherapy and combination therapy of LMV and IFN were predicted to more effectively reduce the HBV and HDV viral loads in the case of super-infection scenarios when compared with the co-infections.
Abstract: Background
Mathematical models have shown to be extremely helpful in understanding the dynamics of different virus diseases, including hepatitis B. Hepatitis D virus (HDV) is a satellite virus of the hepatitis B virus (HBV). In the liver, production of new HDV virions depends on the presence of HBV. There are two ways in which HDV can occur in an individual: co-infection and super-infection. Co-infection occurs when an individual is simultaneously infected by HBV and HDV, while super-infection occurs in persons with an existing chronic HBV infection.
Methodology/Principal Findings
In this work a mathematical model based on differential equations is proposed for the viral dynamics of the hepatitis D virus (HDV) across different scenarios. This model takes into consideration the knowledge of the biology of the virus and its interaction with the host. In this work we will present the results of a simulation study where two scenarios were considered, co-infection and super-infection, together with different antiviral therapies. Although, in general the predicted course of HDV infection is similar to that observed for HBV, we observe a faster increase in the number of HBV infected cells and viral load. In most tested scenarios, the number of HDV infected cells and viral load values remain below corresponding predicted values for HBV.
Conclusions/Significance
The simulation study shows that, under the most commonly used and generally accepted therapy approaches for HDV infection, such as lamivudine (LMV) or ribavirine, peggylated alpha-interferon (IFN) or a combination of both, LMV monotherapy and combination therapy of LMV and IFN were predicted to more effectively reduce the HBV and HDV viral loads in the case of super-infection scenarios when compared with the co-infection. In contrast, IFN monotherapy was found to reduce the HDV viral load more efficiently in the case of super-infection while the effect on the HBV viral load was more pronounced during co-infection. The results suggest that there is a need for development of high efficacy therapeutic approaches towards the specific inhibition of HDV replication. These approaches may additionally be directed to the reduction of the half-life of infected cells and life-span of newly produced circulating virions.
20 citations
01 Jan 2010
TL;DR: In this article, the authors show how the use of these new technologies can promote, in both small and large classes, the knowledge and understanding of statistics in an environment that, although tailored for each student, encourages the student to interact with his/her classmates, creating a vivid environment that enhances their learning potential.
Abstract: Technology is part of the new reality in the educational system. Students use it, and teachers need to find new ways to engage students. Web 2.0 is the turning point in which the World Wide Web can be used to fully enhance the creativity of its users with its many instruments available, such as blogs, social-networking sites, video sharing sites and wiki pages, just to mention a few. The richness and diversity of subjects that Statistics encompasses, together with the WWW, creates an environment of excellence in which students play an active role in the entire learning process. It is our goal to show how the use of these new technologies can promote, in both small and large classes, the knowledge and understanding of statistics in an environment that, although tailored for each student, encourages the student to interact with his/her classmates, creating a vivid environment that enhances their learning potential.
2 citations
01 Jan 2010
TL;DR: The results, obtained through real experimentation of the implemented architecture through an advanced mobility scenario using a real WiMAX testbed, show that the architecture is able to provide QoS under dynamic scenarios, with fast integrated QoS and mobility signaling.
Abstract: Although WiMAX, based on the IEEE 802.16 family of standards, has emerged as one of the major candidates for next generation networks, it is also clear that in the near future, the combination of several technologies will be required. In this sense, the support of mobility in heterogeneous environments, addressing broadband wireless, is one of the main requirements in next generation networks. This chapter presents an architecture based on the recently standardized IEEE 802.21 framework, integrating both mobility and Quality of Service (QoS) mechanisms, and accommodating different wired and wireless technologies, such as WiMAX, Wi-Fi, DVB, and UMTS. This architecture supports seamless mobility in broadband wireless access (BWA) networks, and thus, it is suitable for next generation network environments. The results, obtained through real experimentation of the implemented architecture through an advanced mobility scenario using a real WiMAX testbed, show that the architecture is able to provide QoS under dynamic scenarios, with fast integrated QoS and mobility signaling.
1 citations
TL;DR: In this paper, the connections between extremal indices and stability of Markov chains were investigated, and a close link between the extremal index and geometric ergodicity was found.
Abstract: We investigate the connections between extremal indices on the one hand and stability of Markov chains on the other hand. Both theories relate to the tail behaviour of stochastic processes, and we find a close link between the extremal index and geometric ergodicity. Our results are illustrated throughout with examples from simple MCMC chains.
31 May 2010
TL;DR: This paper aims to demonstrate the efforts towards in-situ applicability of EMMARM, as to provide real-time information about concrete mechanical properties such as E-modulus and compressive strength.
Abstract: (1) Molecular and Environmental Research Centre (CBMA) / Department of Biology / University of Minho, Braga, Portugal (2) BIOCANT Biotechnology Innovation Center, Cantanhede, Portugal (3) CESAM and Biology Department, Aveiro University, Campus Universitário de Santiago, Aveiro (4) Centre for Malaria & Tropical Diseases, Associated Laboratory, Unit of Epidemiology and Biostatistics, Institute of Hygiene and Tropical Medicine New University of Lisbon, Lisbon, Portugal